1. Field of the Invention
The present invention relates to a submersible motor driven pump and, in particular, a liquid petroleum gas (LPG) submersible electric motor driven pump and drive coupling therefor.
2. Description of the Related Art
As the demand for LPG fuel from fleet, government and private usage increases, there has been a simultaneous need in the field for a greater pressure and performance from the LPG pumping system. Moreover, in the conventional LPG systems which utilize suction pumps, vapor lock is a persistent problem and occurs when fuel is pulled beyond its vaporization point, thereby reducing the vacuum necessary to pull the fuel from the storage tank. Moreover, larger tanks and longer pipe runs, which are necessary to meet the increasing fuel demands, only aggravate the problem.
Accordingly, there is a need in the LPG pumping industry to provide a submersible pump which is operative to push the fuel from the tank, thereby effectively moving any existing vapor in the lines to the vapor recovery system. Such a submersible pump would maintain serviceability while staying clear of customers and the forces of nature, making them safer and less obtrusive than external pumps.